| 0,0 → 1,128 |
|---|
| /*------------------------------------------------*/ |
| /* UART functions */ |
| |
| |
| #include <avr/io.h> |
| #include <avr/interrupt.h> |
| #include "uart.h" |
| |
| #define SYSCLK 9216000 |
| #define BAUD 115200 |
| |
| |
| typedef struct _fifo { |
| uint8_t idx_w; |
| uint8_t idx_r; |
| uint8_t count; |
| uint8_t buff[64]; |
| } FIFO; |
| |
| |
| static volatile |
| FIFO txfifo, rxfifo; |
| |
| |
| |
| /* Initialize UART */ |
| |
| void uart_init() |
| { |
| rxfifo.idx_r = 0; |
| rxfifo.idx_w = 0; |
| rxfifo.count = 0; |
| txfifo.idx_r = 0; |
| txfifo.idx_w = 0; |
| txfifo.count = 0; |
| |
| UBRR0L = SYSCLK/BAUD/16-1; |
| UCSR0B = _BV(RXEN0)|_BV(RXCIE0)|_BV(TXEN0); |
| } |
| |
| |
| /* Get a received character */ |
| |
| uint8_t uart_test () |
| { |
| return rxfifo.count; |
| } |
| |
| |
| uint8_t uart_get () |
| { |
| uint8_t d, i; |
| |
| |
| i = rxfifo.idx_r; |
| while(rxfifo.count == 0); |
| d = rxfifo.buff[i++]; |
| cli(); |
| rxfifo.count--; |
| sei(); |
| if(i >= sizeof(rxfifo.buff)) |
| i = 0; |
| rxfifo.idx_r = i; |
| |
| return d; |
| } |
| |
| |
| /* Put a character to transmit */ |
| |
| void uart_put (uint8_t d) |
| { |
| uint8_t i; |
| |
| |
| i = txfifo.idx_w; |
| while(txfifo.count >= sizeof(txfifo.buff)); |
| txfifo.buff[i++] = d; |
| cli(); |
| txfifo.count++; |
| UCSR0B = _BV(RXEN0)|_BV(RXCIE0)|_BV(TXEN0)|_BV(UDRIE0); |
| sei(); |
| if(i >= sizeof(txfifo.buff)) |
| i = 0; |
| txfifo.idx_w = i; |
| } |
| |
| |
| /* UART RXC interrupt */ |
| |
| SIGNAL(SIG_UART0_RECV) |
| { |
| uint8_t d, n, i; |
| |
| |
| d = UDR0; |
| n = rxfifo.count; |
| if(n < sizeof(rxfifo.buff)) { |
| rxfifo.count = ++n; |
| i = rxfifo.idx_w; |
| rxfifo.buff[i++] = d; |
| if(i >= sizeof(rxfifo.buff)) |
| i = 0; |
| rxfifo.idx_w = i; |
| } |
| } |
| |
| |
| /* UART UDRE interrupt */ |
| |
| SIGNAL(SIG_UART0_DATA) |
| { |
| uint8_t n, i; |
| |
| |
| n = txfifo.count; |
| if(n) { |
| txfifo.count = --n; |
| i = txfifo.idx_r; |
| UDR0 = txfifo.buff[i++]; |
| if(i >= sizeof(txfifo.buff)) |
| i = 0; |
| txfifo.idx_r = i; |
| } |
| if(n == 0) |
| UCSR0B = _BV(RXEN0)|_BV(RXCIE0)|_BV(TXEN0); |
| } |
| |